The present application generally relates to an apparatus for synthesizing compounds and, more particularly, to an apparatus that can synthesize compounds and, further, be used as an abatement process for harmful and toxic waste.
It has long been recognized that chemical synthesis can be achieved by opening a given chemical bond in one or more molecules to allow the recombination of such molecules into new compounds. This opening has been typically achieved by heating molecules under pressure or by the use of catalysts. Heating under pressure, however, requires special equipment, such as a pressurized reaction vessel. Catalysts on the other hand often create undesirable or toxic by-products, which must then be disposed of or destroyed.
Typical chemical abatement processes similarly involve heating but at much higher temperatures. In high temperature incineration, the toxic chemicals are heated to temperatures typically on the order of about 1000xc2x0 C. or greater. However, even with these extreme temperatures, not all the chemicals are destroyed which may result in discharge of the residual toxic substances into the environment. Other methods of chemical abatement include the use of landfills, but great care must be taken to avoid contamination of ground water in the region of the land fill. However, neither of these processes are preferred for destroying gaseous waste products, such as produced in the microelectronics industry, because residual toxin gases may escape into the environment.
More and more processes produce toxic by-products. For example, in the semiconductor fabrication industry, effluent streams of nitrogen, freons, fluorinated carbons, silanes, and the like are produced. As previously noted, however, high temperature incineration is not suitable for gaseous waste products as incineration does not necessarily eliminate the toxic by-products completely. With dwindling available land fills and concerns for the environment, this increase in production of hazardous waste is becoming a national and global problem.
Consequently, there is a need for simpler chemical synthesis and chemical abatement processes.
Accordingly, the present invention provides for an apparatus which uses a rotating arc for either chemical synthesis or chemical abatement.
In one form of the invention, a chemical abatement apparatus includes a processing chamber and a secondary chamber which is in communication with the processing chamber. The processing chamber is configured to generate an arc in the processing chamber. A magnetic field generator selectively generates a magnetic field in the processing chamber, which induces the arc generated in the processing chamber to rotate. The apparatus further includes at least one injection port for introducing at least one waste medium into the processing chamber and into the rotating arc whereby the rotating arc transforms the chemical constituents in a plasma and disassociates the chemical constituents comprising the waste medium into a non-toxic form which thereafter flows into the secondary chamber. The secondary chamber is configured to quench the plasma when the plasma is in the secondary chamber to maintain the disassociation and thereby reduce the reactivity of the chemical constituents.
In one aspect, the apparatus includes a second injection port for introducing a quenching medium into the secondary chamber to quench the plasma. For example, the second injection port is preferably adapted to inject water or water vapor into the secondary chamber. Preferably, the secondary chamber includes a plurality of the second injection ports.
In other aspects, the magnetic field generator comprises a coil which extends around at least a portion of the processing chamber. Preferably, the magnetic field generated by the coil has sufficient magnitude to rotate the arc to form a solid plasma disc. Alternately, a permanent magnet can be used to generate the magnetic field.
In yet other aspects, the apparatus includes an anode and a cathode which are positioned in the processing chamber and which are configured to generate the arc therebetween.
In further aspects, the processing chamber includes a third injection port and a cathode housing which extends around the cathode. The third injection port is used to inject an inert gas between the cathode and the cathode housing to form a sheath around the cathode which protects the cathode from reactants in the processing chamber from reacting with the cathode.
In another form of the invention, a chemical synthesis apparatus includes a processing chamber and a secondary chamber which is in communication with the processing chamber. The processing chamber is configured to generate an arc in the processing chamber. A magnetic field generator selectively generates a magnetic field in the processing chamber which induces the arc in the processing chamber to rotate. The apparatus further includes at least one injection port for injecting at least two mediums into the processing chamber and into the rotating arc whereby the rotating arc transforms the mediums into plasma whereby the elements comprising each medium are energized to a more reactive state and consequently associate to form a desire compound. The compound, thereafter, flows into the secondary chamber, which is configured to quench the compound when the compound is in the secondary chamber to stabilize the compound.
In other aspects, the secondary chamber includes an expanded portion to permit the molecules forming the compound to expand thereby further stabilizing the compound. Preferably, the compound is quenched when the medium enters the expanded portion of the secondary chamber.
According to yet another form of the invention, a method of chemical abatement includes generating a rotating arc, exposing a waste medium to the rotating arc to disassociate the chemical constituents of the waste medium into a non-toxic form, and quenching the chemical constituents in the non-toxic form to stabilize the disassociated state of the chemical constituents.
In one aspect, the method of chemical abatement further includes expanding the disassociated chemical constituents in their non-toxic form to further stabilize the chemical constituents. For example, expanding may include directing the chemical constituents into a chamber with an expanded portion.
In other aspects, quenching includes exposing the chemical constituents in their non-toxic form to one of water and water vapor. Preferably, the chemical constituents are expanded and quenched substantially simultaneously.
In yet another form of the invention, a method of chemical synthesis includes generating a rotating arc exposing at least two medium to the rotating arc to energize the mediums to a more reactive state whereby the mediums associate to form a chemical compound. The chemical compound then quenched to stabilize the chemical compound in its existing form.
In this manner, the present invention provides for a method and apparatus in which a rotating arc can be used to energize elements for forming compounds therefrom or to energize chemical constituents of a waste compound to cleave the bonds between the chemical constituents to form non-toxic constituents. The resulting compound or non-toxic constituents are then stabilized in their respective forms by quenching.